App hangs after updating to yosemite

I have an app that I built on 10.8. I just upgraded to yosemite and now when I try to launch it (either from the build or from xcode 6.2 it hangs. This is a cocoa application with applescript. All I see in the console window is “2015-03-19 18:53:49.259 MyXML[33020:1471037] Attempt to set a non-property-list object null as an NSUserDefaults/CFPreferences value for key fileDestination”

Anybody have any idea’s?

That’s telling you that you’re somewhere trying to set a defaults value for the key fileDestination, but you’re passing either missing value or something illegal in a property list. Does that help you track it down?